Miley Cyrus may have posted a picture of a diamond ring on her Twitter feed but the Hannah Montana star is not engaged to her Hunger Games beau Liam Hemsworth, according to US weekly. A source close to the young actress told the publication that the ring is definitely not an engagement ring.When Miley, 19, posted the picture, it was intended to show her Twitter followers the recent manicure that she'd just had done and was accompanied by a message that read "I am soooo obsessed with jennahipp nail foundations! It looks so chic and classic!" Cyrus has been dating the Australian hunk, 22 since 2009 and they have plenty to celebrate together at the moment, with Liam's most recent film, The Hunger Games released on the weekend and achieving the highest opening box office weekend for any non-sequel in U.S. history. However, she may be wearing an enormous rock on her wedding finger but there's no word from Miley or Liam on an engagement just yet.On Saturday night (March 24, 2012), the couple were spotted out at Muhammad Ali's Celebrity Fight Night Xiii event in Phoenix, Arizona, and Miley was wearing the ring, which sparkled against her peach-colored dress. The floor-length dress, which had a daring thigh-high split up the right leg, drew comparison to the dress that Angelina Jolie wore to the Oscars. Jolie's dress choice resulted in her right leg garnering almost as many column inches the next day, as the award winners.